Valemount avalanche and snowpack observations

[CUSO]

Thanks,
They never went over the acronyms when I took mine. My group's is getting a refresher Sunday.

I guess this thread may not be helpful for some that haven't taken the AST yet.

I guess that's ok. Carry on.

Thats fine this sled for avalanche obs and info. Anything i read so far is taught in any Ast course.

This is not just about pits. Winds, precip type/amounts and avalanche observations are all very relevant and important as well.

 

[Valemount Skier]

Taken from a posting by rknight111 (Ron) on another thread on Saturday December 13 at 6:48pm
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Caution, we were riding at Clemina today and there was an avalanche at Danger Basin, and several others. Be careful people, peeps were hitting the big hills without thinking.

 

[Depsnolvr]

Allen Creek today had a lot of larger Sz2.5 and one very large sz 3-3.5 from a day or so ago. All failing on steep and loaded apects from N-E some natural and some trigger remotely or accidentally.

Ride safe

 

[team-x]

Curtis are you going to get out there and make a video of the snow pack or too much going on to get out there right now?

 

[Depsnolvr]

I hope to get out on wednesday and intend on doing some video

 

[Valemount Skier]

Sunday December 21

Went to Clemina and skied the trees below Dixon's Glacier. First off, thanks to Curtis and his AST class for breaking the lower access trail to the hill-climb area. This access heads left across the bottom of the 3rd block up and stays in the trees to avoid the overhead exposure of the traditional higher route. A small slab had pulled out below the cliffs above the traditional higher route.

Very high winds and lots of snow transport in the alpine and exposed areas. Our 12cm-15cm deep tracks across the lake were totally blown in after not much more than 4 hours.

Dug a pit in the trees on a 35 degree north-facing aspect at about 6100 feet. Snow depth about 175cm. While we could see and feel a couple of stiffer slabs in the top 100cm, nothing was reactive to compression tests at normal striking force. We could generate a failure down about 40cm, but only by risking broken bones in our hands. There was no rain-crust in the snowpack at this location.

 

[Vance Matheson]

I hope to get out on wednesday and intend on doing some video

A great thread, the informative videos we enjoy watching do work.

 

[Dannyturbo]

how she lookin out there fellas, the bulletins are lookin kinda dicey

 

[Valemount Skier]

New Years Day

Toured up south-east ridge of Mt Trudeau (left-hand ridge as seen from town). Buried surface hoar layer that has been highlighted in recent avalanche bulletins was present from about 5,500 feet up to where I stopped at about 6,500 feet. Layer was about 20cm down in a pit at about 6,500 feet on a 30 degree east facing slope, and was failing with a planer shear on first tap from elbow. This location was the same aspect and elevation as the lake on Upper Westridge. Avalanche Canada's danger rating for Friday has increased to high as new snow is expected to begin overloading this layer.

Here is an interesting article on "danger and risk" from the Utah Avalanche Center's forecaster blog
Blog: Drift into Failure...or, Mathematics and a Few Thoughts on Risk | utahavalanchecenter.org

 

[Depsnolvr]

Hey guys

The inversion on Thursday, January 8 caused some substantial settlement in the new snow that we had received during the previous week and left a nasty little crust above 1850m.

The mid December surface hoar is still quite prevalent in sheltered locations. I have found it anywhere from 25-50cm down depending on loading. On our tests today, the new snow above this layer does not seem to be settled enough yet to produce a solid slab that would inhibit propagation although with these mild temperatures, this would not take much to stiffen up this upper soft slab. We were getting repeatable moderate sudden planer results on this layer on any sheltered northerly aspects. Extended column test did not propagate but I dont think it will take much to stiffen this upper slab.

Some pretty extreme slope testers out there and no new avalanches were seen over my last two days of riding.

Ride safe everyone and check www.avalanche.ca before your ride.

 

[Depsnolvr]

This video goes to show the importance of understanding the true extent of persistent weak layers. The typical "mount everest" type slopes are not the only ones that can surprise us.

As sledders, the terrain we can cover in a matter of hours demands that we pay attention. We must be aware and observe our surroundings and continually test the snow that we are riding on.

Thank you very much to the great group of riders that donated the footage. This is something that can really raise awareness within our community.

Ride safe everyone

https://www.youtube.com/watch?v=yhhAUcvXa3Q

 

[scotts]

Went up westridge yesterday and dug a test pit on a 30 degree North/East aspect at 2200 meters , fairly sheltered with 180cm total snowpack depth, compaction testing yielded repeatable CTH 21 SP "Sudden Planer" failure down approximately 35cm on buried decomposing Surface hoar and 1-3mm facets. We also found a deeper instability at 65cm down which showed a shovel CTH 25 also Sudden Planer,again failing on 1-3mm facets, also repeatable in our second test, I wasn't able to identify any Surface Hoar present at this interface but that may be due more to lack of experience than it not being present. Below this the snowpack seems well consolidated! Didn't observe any recent natural or machine triggered avalanches in our travels over the weekend!

 

[Valemount Skier]

Saturday January 17

Ski touring in one of the North Thompson side drainages. Didn't do any full pits, but did about 6 "hand pits" in somewhat open trees on north-ish facing slopes as travelled from 5000 feet up to treeline. Surface hoar layer present and reacting in all tests, down about 45cm. As elevation increased, it seemed to take a bit more force to trigger the layer.

 

[VARDA]

Fully agree with the above. Treeline elevations the surface hoar continues to be a big issue for us tree folk. Clemina has up to 25mm SH buried on average 50cm down. High moderate or low hard sudden planar results around the 1600-1700 mark

 

[Valemount Skier]

Sunday February 1

Toured up the middle fork of the McLennan River (west of Valemount, accessed from end of Westridge FSR). Most of the day was spent in forest or down in creek. Once farther up the valley, noticed quite a few point-releases on steep, rocky, south-facing slopes likely caused by Saturday's sunshine. The bit of actual skiing that we did had about 10cm-15cm on top of the rain crust. New snow was not bonding well to the rain crust. Second-hand report Saturday at a different location said the same.